Lighting 101

There have been a lot of new people here lately, asking all kinds of questions about what type of lighting to use over a reef tank. I decided it was easier to write this up then answer the same questions a million times in a million threads.

Mods- Please sticky this or move it to the articles section

Feel free to add other information, and no this isn't a holy grail or a final answer, but it should help in the research everyone should do on this topic

A Quick and Dirty introduction to Reef Lighting

Disclaimer: I am merely trying to put everything I learned researching the different types of reef lighting in an attempt to cut down on the ‘How much lighting to I need’ and ‘Can I use these cheap Chinese LED’s for my SPS reef tank’ threads

First, why do we need such an expensive light fixture over our reef tanks? The answer lies here:

Basically, corals are like plants, they get their energy from light. In order for this to happen, the light needs to be in the right ‘color’ or specturm. Not only does it need to reside in the right spectrum, but whatever is providing it must penetrate through the water in our tank to get to our corals (it is harder for light to penetrate water then say air)

Types of Lighting:

There are currently three main types of lighting for a reef tank. Metal Halide, T5 Fluorescent, and LED

Metal Halide

These are used primarily by old school hobbyists or those with very large or very deep tanks, as you get more coverage both from a spatial standpoint and a depth penetration stand point. Metal Halide lighting has been used for quite a while in this hobby, and there are a plethora of fixtures and bulbs available. Bulb colors range from 5K (very yellow/white) all the way up to 20K + (very blue).

It should be noted that there are two main drawbacks to this type of lighting:
Bulb replacement/cost: At least once a year these bulbs must be replaced, and depending on the brand of bulb you use, you are looking at anywhere from $50-$100 per bulb
Energy Consumption - Metal Halides will use far more energy both T5’s and LED’s

T5 Fluorescent Lighting

T5 Fluorescent lighting uses bulbs very similar to the ones you see in offfices and workshops. Please note: the bulbs and fixtures used in offices and workshops WILL NOT WORK for our tanks.

T5 lighting can be used on its own, or in conjunction with metal halide lighting. In fact, there are many commercially available lighting fixtures that use both metal halide bulbs and T5 bulbs

T5 bulbs work basically the same way as metal halide as far as spectrum goes. There are various ‘Daylight’ bulbs that are white, and various ‘actinic’ bulbs that are blue. It is the actinic bulbs or the bluer color that causes the colors in coral to ‘pop’. There are also some purple bulbs that are used to increase coral coloration

T5 bulbs need to be replaced every 6-9 months once they have reached the point of ‘phase shift’ where the light put out shifts into the red spectrum. This shift will encourage the growth of nuisance algae.

T5 lighting is more efficient than Metal halide lighting energy wise, but less efficient than LED. A rough approximation of watts needed is 3-5, and a quality fixture will have an individual reflector for each bulb in the fixture

There are also T8 and T12 fixtures that were used in the past. Generally speaking, these fixtures are not capable of supporting corals long term, and are best left to the history books. Bulb choices will be limited, and the fixtures themselves will use quite a bit of power

LED Lighting

LED lighting is the ‘new frontier’ of reef lighting, and it will be the lighting choice of the future once the cost of the fixtures come down. LED fixtures obviously use LED’s to generate light.

There are two main led fixture types, those that use 1 Watt LED’s and those that use 3 Watt LED’s. Fixtures using 1 Watt LED’s are primarily used in smaller, shallower tanks (we’ll say less than 20 inches for the sake of this beginner primer). In any tank deeper than 18 inches, I would only consider fixtures that run 3 Watt LED’s

Again, much like metal halides and T5’s the LED fixtures will have a combination of white and blue LED’s - some of the higher end fixtures have also started incorporating other colors such as violet, green, cyan, red, and orange.

If you are electrically inclined, there are may sites that offer do it yourself kits that will allow you to create a fixture of your own that is cheaper than buying a commercially available fixture

As far as the magic wattage question goes, there is no simple answer, it really depends on ones setup for LED’s. When I started my tank up, I had a combination Metal Halide / T5 fixture that was rated at 1000 watts. I replaced that with 225 watts of 3 Watt LED’s and I cannot run them more than 50% - so I basically replaced 1000 Watts halides and T5’s with ~112 watts of LED. There are also no bulbs to replace, most commercially available LED’s are rated at 50,000 hours of life

Hopefully, this primer has served to answer some of the basic questions about reef lighting. Spend some time over at Advanced Aquarist and read up on lighting, it is probably the most important part of this hobby. Your lighting fixture will also probably be the largest investment in your hobby. I have spend more on lighting than I did for my 6 foot long 180 gallon reef tank. Research, Research, and Research again before making your purchase

do the stunner led strips, the Ecoxotic Panorama Pro, Innovative Marine Skkye Light, and Current USA TrueLumen Pro LED work at all on say smaller tanks under 40gal. If i understand with leds its not watts you need its more par and lumens you need? Those led fixtures are real $$$ 300 plus. but the strips are less $$$ and you can work at getting 1 or 2 at a time instead of a $300 dollar plus led fixture. I guess what i am trying to get at is its easy to under stand 3-5w per gal on a t-5 but no one really knows how much of anything leds need. 10 6watt leds on the little stunner strips would be 60 watts total which in theory should be enough for a 50-60 gal reef tank.

The problem there is most of the stunner strips to not have optics, so you aren't going to get any real depth penetration from them. For a 40 gallon breeder, I would look at PAR38 bulbs, you could probably get away with 2 of them, and they plug into standard light bulb sockets, mounting options are only limited by your imagination. You'd need at least that much $$ in stunner strips, probably more

We are really really new to salt water tanks. We have had tanks for over 10 years but this is our first Salt Water.. I noticed you have a 180 gallon tank and we also have that size. I was wondering what kind of LED light you have. I noticed you said it was 225 Watt of 3 Watt LEDs but you have to make sure it is the right LED lights. I did some research but I'm really confused as to what we need.

We are not sure if we are going to put coral in the tank yet but I figure we should get a light that will allow us to do so otherwise we will just need to buy another light.

You could also look into the AI Vega fixture, it is a little more expensive, but it is a full spectrum unit with a lot more control available. Other fixtures I would look into are the Kessil Tuna Blue, Maxspect Mazzara, and the EcoTech Radion line

Before you actually buy lighting for your tank, you should really try to decide if you plan on keeping a reef tank or a fish only tank. LED's are not cheap, you would be looking at something like $1200 or so for the setup that I have, and it would be complete overkill if you are not planning on keeping coral or other photosynthetic animals. If all you are keeping is fish, the much cheaper T8 bulbs that most hoods are sold with would be more than sufficient

You could also look into the AI Vega fixture, it is a little more expensive, but it is a full spectrum unit with a lot more control available. Other fixtures I would look into are the Kessil Tuna Blue, Maxspect Mazzara, and the EcoTech Radion line

Before you actually buy lighting for your tank, you should really try to decide if you plan on keeping a reef tank or a fish only tank. LED's are not cheap, you would be looking at something like $1200 or so for the setup that I have, and it would be complete overkill if you are not planning on keeping coral or other photosynthetic animals. If all you are keeping is fish, the much cheaper T8 bulbs that most hoods are sold with would be more than sufficient

Thanks for the great post, the question I have is about all the different ratings that lights have listed. Could you explain to me what the importance of watts, lumen, kelvin and wavelength (I understand this is the wavelength of the color but do you want different ranges for the blue/other colors)? Are all of them important or do some of these things matter more?

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